Both JACK and LV2 are multiplatform, but there are Windows build problems for JACK atm. I'm unaware as to the current state of things regarding macOS. However, Carla is multiplatform can do it all internally.
There are a limited number of binary LV2 bundles available for Windows n macOS. That number has been slowly increasing, though just a fraction of LV2 use CV ports so far, but it is early days yet.
